Vibrato is one of those techniques that we're all expected to be able to master as we advance in our playing. For some it seems to come naturally and only slightly refined, for others it needs intentional training. (I found it tricky myself). Here's a short article that explains what vibrato is, some general guidelines around how it can be used most effectively in playing and some steps to help you start developing your own unique style.
Do you have an tips or tricks that you found really helpful when learning and applying vibrato that you'd like to share with the group??